protoniboron11

Protoniboron11 is a proposed chemical concept referring to a proton-bound boron-11 containing species. The name suggests a boron-containing cluster or molecule in which a single proton is attached to a boron-11 nucleus or to a boron-11 framework. Because boron-11 is the predominant stable isotope of boron, the designation is often used in discussions of isotope effects on bonding and spectroscopy.

Structures proposed for protoniboron11 include a monoprotonated boron hydride such as HB11 or a protonated boron cluster [HB11H]+, where the proton is localized on a boron center or delocalized across the cluster. The exact geometry depends on the size and hydrogenation of the boron core; theoretical studies predict several low-lying isomers with B–H and B–B bonding patterns typical of boron hydrides and boron clusters.

Most discussions of protoniboron11 are theoretical. Computational investigations have explored its potential energy surface, proton affinity, and vibrational spectra to identify distinctive features that could be probed by gas-phase spectroscopy. Predicted infrared signatures include B–H stretching bands in the mid-infrared region and characteristic boron-boron stretch modes sensitive to protonation.

Experimentally, no isolated, unambiguous synthesis has been widely reported, but targeted experiments using mass spectrometry and cryogenic ion spectroscopy could in principle detect protoniboron11 as a transient ionic or neutral species under controlled conditions. The concept serves as a theoretical tool for studying proton transfer, isotope effects, and bonding in boron-rich systems.